Cats with chronic dual Brugia malayi and streptococcal infections will be monitored to determine to what extent limbs will maintain their elephantoid condition. Simultaneously, microfilariae levels will be compared to those of control animals infected only with B. malayi. Adult worms recovered from both groups will be correlated with the microfilariae levels. Regional lymph nodes from cats with persistent edema and from cats with very transient edema will be compared. Injection of viable streptococci and Sporothrix schenckii into the vascular and lymphatic system of cats recently treated with diethylcarbamazine will determine if dead Brugia can serve as a nidus for culture of opportunistic microorganisms. We will attempt to define the role of venous-lymphatic shunts in the drainage of excess fluids produced in dual Brugia-streptococcal infections by the use of corrosion specimens. Alternately, alcian blue or colloidol carbon will be used for infusion of affected regional lymph nodes. To determine the value of the patas monkey in studying filaria-induced lymphatic dysfunction, a limited number of monkeys will be infected with B. malayi. Surgical removal of regional lymph nodes at intervals will demonstrate development of the parasite and effects of the maturing worms on the lymphatics.